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Epic exoplanet 61 EP

LHS 1678 d

RA 68.1790° · Dec -39.7909° · exoplanet

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Score breakdown

· 7 badges
61 pts · Epic
Epic 78 pts → Anomaly
  • Earth-sized +16
  • Two suns in its sky +12
  • Tidally locked +10
  • Orbits a red dwarf +8
  • Multi-planet system +6
  • Confirmed exoplanet +5
  • Found by TESS +4
Total score 61

17 more points to reach Anomaly.

Badges

  • Confirmed exoplanet · +5
  • Earth-sized · +16
  • Tidally locked · +10
  • Multi-planet system · +6
  • Found by TESS · +4
  • Orbits a red dwarf · +8
  • Two suns in its sky · +12

Trivia

What makes it special

  • Earth-sized. Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

What it actually is

  • Hugging its star. It orbits closer to its star than Mercury does to the Sun, completing a lap in less time than Mercury takes.
  • What it is made of. Its density says rock, though lighter than Earth's mix: probably less iron, or a thick shell of water and ice over the top.
  • Crowded system. One of at least 3 planets orbiting its star.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 12.6 it is far too faint for the eye: this one belongs to cameras and long exposures.
  • Southern sky. It rides the southern half of the sky — an easier target the further south you are.
  • Best time of year. It stands highest in the middle of the night around November — that's when to go looking.

Properties

density gcc
5.28
diameter km
12513.8322
discovery facility
Transiting Exoplanet Survey Satellite (TESS)
discovery method
Transit
discovery year
2024
dist ly
64.8339
eccentricity
0.036
eq temp k
462.95
host star teff
3490
inclination
88.31
insolation
9.1
mag
12.6
mass earth
0.907
multi star system
yes
name
LHS 1678 d
orbital period days
4.9652
radius earth
0.981
semi major au
0.04
spect
M2.0 V
sys num planets
3
sys num stars
2
tidally locked
yes
tidally locked inferred
yes

About LHS 1678 d

LHS 1678 d is an epic exoplanet. It lies about 64.8 light-years from Earth, shines at apparent magnitude 12.6, has spectral type M2.0 V and has an equilibrium temperature near 463 K.

Genuinely comparable to Earth in size. Worlds in this narrow band are the ones every next-generation telescope is being pointed at.

How to see it

At apparent magnitude 12.6, it takes a larger telescope or a long-exposure image to capture.

Like any astronomical target, LHS 1678 d is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. The visibility panel above works out tonight's viewing window for your saved location.

Why LHS 1678 d is an epic exoplanet

LHS 1678 d scores 61 points on Spacedle's rarity scale, which places it in the epic tier. Another 17 points would lift it into a rarer tier.

That score comes from 7 science badges — Confirmed exoplanet, Earth-sized, Tidally locked, Multi-planet system, Found by TESS, Orbits a red dwarf and Two suns in its sky — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.